Answer in brief
CVE-2025-39802 records a Unknown severity vulnerability in lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=773426f4771bdd82ac5c834bf4c1775315c73a46 <87bdfba903be7084cb3ee04032b14a81181fe413 || >=773426f4771bdd82ac5c834bf4c1775315c73a46 <52c3e242f4d0043186b70d65460ba1767f27494a | 87bdfba903be7084cb3ee04032b14a81181fe413, 52c3e242f4d0043186b70d65460ba1767f27494a |
| Linux/Linuxgeneric | 6.16 | Not reported |
Published upstream
Sep 15, 2025
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
In the Linux kernel, the following vulnerability has been resolved: lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts Restore the SIMD usability check that was removed by commit 773426f4771b ("crypto: arm/poly1305 - Add block-only interface"). This safety check is cheap and is well worth eliminating a footgun. While the Poly1305 functions should not be called when SIMD registers are unusable, if they are anyway, they should just do the right thing instead of corrupting random tasks' registers and/or computing incorrect MACs. Fixing this is also needed for poly1305_kunit to pass. Just use may_use_simd() instead of the original crypto_simd_usable(), since poly1305_kunit won't rely on crypto_simd_disabled_for_test.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2025-39802 records a Unknown severity vulnerability in lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=773426f4771bdd82ac5c834bf4c1775315c73a46 <87bdfba903be7084cb3ee04032b14a81181fe413 || >=773426f4771bdd82ac5c834bf4c1775315c73a46 <52c3e242f4d0043186b70d65460ba1767f27494a | 87bdfba903be7084cb3ee04032b14a81181fe413, 52c3e242f4d0043186b70d65460ba1767f27494a |
| Linux/Linuxgeneric | 6.16 | Not reported |
Published upstream
Sep 15, 2025
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
In the Linux kernel, the following vulnerability has been resolved: lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts Restore the SIMD usability check that was removed by commit 773426f4771b ("crypto: arm/poly1305 - Add block-only interface"). This safety check is cheap and is well worth eliminating a footgun. While the Poly1305 functions should not be called when SIMD registers are unusable, if they are anyway, they should just do the right thing instead of corrupting random tasks' registers and/or computing incorrect MACs. Fixing this is also needed for poly1305_kunit to pass. Just use may_use_simd() instead of the original crypto_simd_usable(), since poly1305_kunit won't rely on crypto_simd_disabled_for_test.
Quoted source text, attributed separately from HOL analysis.